Treatment of cinematographic films



W. B. WESCOTT.

TREATMENT OF CINEMATOGRAPHIC FILMS.

APPL |CAT!0N FILED 1AN.28. 1918.

1,380,279. Patented May 31, 1921.

UNITED STATES PATENT OFFICE.

WILLIAM BURTON" WESCOTT, WELLESLEY, MASSACHUSETTS, ASSIGNOE T0 KAL- MUS, COMSTOCK & WESCOTT, INCORPORATED, 015 BOSTON, MASSACHUSETTS, A. COR,

rons'rron or MASSACHUSETTS.

TREATMENT OF CINEMATOGRAPHIC FILMS.

Specification of Letters Patent.

Patented May 31, 1921..

Application filed January 28, 1918 Serial No. 214,086.

America, and resident of Wellesle in the county of Norfolk and State of assachusetts, have invented new and useful Improvements in theTreatment of Cinematographic Films, of Which the following is a: specification. I

This invention relates to the treatment of cinematographic films and more particularly to a particular phase of a method of continuous treatment such as disclosed for example in my prior application, Serlal No. 205,999, filed December 9, 1917.

In subjecting a film to a method of continuous treatment such as disclosed 1n my prior application, the film is continuously fed through a series of compartmentsrespectively containing developing, washing, fixing, drying and other fluids. In some cases it is desirable to feed the film up wardly out of a body of liquid, as when feeding the film from a liquid compartment to another compartment, and I have {found that many faulty films have been rendered faulty by employing improper or madequate means for cleaningor drying the film as and after it emerges from the liquid.

As the film emerges from the liquid, in feeding it upwardly out of a body of liquid, a thin coating of the liquid clings to the sides of the film and it is usually desirable to remove this coating of liquid either in whole or in part. I For example, when passing the film from the developing tank to the wash tank intermediate the developing and fixing tanks it is desirable to remove the coating of developer clinging to the film so that it W1 ll not be carried over into the Wash tank in appreciable quantity. Also when passing the film from a wash tank to a drying chamber it is desirable to remove the major portion of the liquid clinging to the film before the film is subjected to the drying process so that the film will dry more quickly and uniformly.

Moreover, a film of oil, dust and other foreignsubstances unavoidably forms on the surface of the liquid in the various tanks and as the photographic strip passes out of the body of liquid throu h this film the film clings to the strip. $711 ile this is objectionable in feeding from any tank, inasmuch as the particles of dust may become embedded in the photographic emulsion, it is particularly objectionable in feeding from a wash tank to .a drying chamber for the reason that the foreign substances are then dried into and on the emulsion.

Various methods for overcomingthe aforesaid difiiculties have been tried but without satisfactory results. Squeegee mechanism comprising rubber rollers, chamois belts, etc., has been employed, but the rollers tend toiembed the particles of dust and dirt in the emulsion and the chamois belts tend to drag the particles along the film and scratch the emulsion.

It is'the object of the present invention to provide a novel method of treating a photographic film by which the film may be cleansed, dried or otherwise treated without coming into contact with any mechanical parts of apparatus. The treatment is effected by flowing a fluid along the film as or after the film emerges from the body of liquid or by projecting a spray against the film. The fluid employed may be either liquid or gaseous, and in the preferred form of the invention liquid and gaseous fluids are successively employed. For cleansing and drying purposes pure water and air may be employed as the treating fluids, respectively, but when chemically treating or dyeing a film according to the present invention suitable chemical or dyeing solutions or mixtures are employed.

In the accompanying drawings, which illustrate one embodiment of my novel apparatus and one manner of performing my new method.

Figure 1 is a side elevation of the apparatus, the tanks being shown in section; and

Fig. 2 is an end elevation of the apparatus.

The illustrations, which are diagrammatic in character, show a tank 1 divided by arpassed thereover from one to the other compartment as for example in the direction of the arrows in Fig. 1. As shown in Fig. 2 these pulleys may be provided with peripheral grooves 9 and 10 at opposite sides of the film to receive cables (not shown) arranged to drive the pulleys so as to relieve the film from the strain of driving the pulleys. all as more fully set forth in my aforesaid application.

The film of foreign material unavoidably formed on the surface of the liquid under commercial conditions of operation is prevented from being carried off with the photographic strip, according to the present invention, by flowing a fluid along the strip as or after the strip emerges from the liquid or by projecting a siray against the strip and preferably by owing a liquid downwardly around the strip at the surface of the body of liquid so that the liquid will spread outwardly from the point of emergence of the strip from the body of liquid along the surface of the body of liquid, thereby carrying the film away from the point of emergence and cleaning the surface of the body ofliquid in this region. By also causing the stream of liquid to contact with the picture strip before it reaches the surface of the body of liquid any foreign substance clinging to the strip may be rinsed off.

As illustrated in the drawings a simple means for carrying out my improved method comprises a pair of perforate pipes, the respective pipes 11 and 12 of which are disposed on opposite sides of the film 1 with their perforations directed downwardly, together with a supply pipe 13 for supplying fluid to the pipes 11 and 12. When the perforations in the pipes 11 and 12 are directed somewhat inwardly toward the film F the streams of liquid engage the film and then flow downwardly along the film. thereby not only clearing the surface of the body of liquid about the point of emergence of the film but also rinsing from the film any particles of dust or other foreign substance carried from the body of liquid, whereas if the perforations are directed directly downwardly or somewhat outwardly from the film only the surface clearing function is attained. When flowing ythe streams of liquid downwardly along the film gently the streams do not agitate the surface of the body of liquid to any appreciable extent but merely flow outwardly from the film along the surface of the body of liquid pushing the film of foreign substance away from the point of emergence of the photographic film.

Under extremely unfavorable conditions the liquid remaining on the film after passing the liquid spray as above described is not entirely clean and if carried into a succeeding body of liquid or if dried upon the film tends to decrease the quality of the finished film. I therefore propose to employ, in conjunction with the liquid spray. a spray of air of other gaseous fluid which is adaptcd to blow off the adhering coating of liquid at least in major part. While the spray of air or the like may be directed against the film at any convenient angle it is preferably directed obliquely against the film in a direction opposite to the motion of the film, so that the liquid on the film is forced backwardly along the film and caused to flow off at the sides. When the major portion of the liquid is blown from the film in this fashion the film may be much more quickly and uniformly dried, and the present invention is therefore particularly applicable in treating a film as it passes from a liquid tank to a drying chamber.

The illustrated means for directing the spray of air or the like against the film comprises a pair of perforate pipes, the respective pipes 11 and 15 of which are disposed on opposite sides of the film F with their perforations directly obliquely toward the film in a direction opposite to the direction of film motion. together with a pipe 16 for supplying fluid to the pipes 1-1 and 15 under pressure.

While certain important objects of the present invention are attained only by using the liquid and gaseous sprays conjunctively as described. unique and useful results may also be obtained by using either the liquid or the gaseous spray independently. Moreover. instead of employing water and air in the liquid and gaseous sprays respectively I may employ chemical or dyeing compounds or mixtures for chemically cleaning, drying or otherwise treating films. the application of the fluids in the form of a spray rendering it. possible to regulate and control the action of the liquid or gas with marked facility and accuracy.

I claim:

1. The method of treating a cinematographic film as it emerges from a body of liquid comprising directing a fluid stream downwardly along the film immediately above the body of liquid so that the stream will spread outwardly at the surface of the liquid and carry any substances floating on the surface of the liquid away from the place where the film emerges.

2. In the chemical treatment of a cinematographic film after ex )osure, a method which comprises first bathing the film with a liquid jet and then blowing off the surface liquid with a gaseous jet.

3. The method of treating a cinematographic film comprising passing the film first through a liquid stream and then through a gaseous stream, each stream being directed obliquely against the film in the direction opposite to the motion of the film.

i eso eze a 4. The method of cleaning a cinematothe surface of the liquid away from the graphic film as it emerges from a body of place where the film emerges, and a removliquid comprising flowing a liquid stream ing the liquid from the film after it leaves 10 downwardly along the film immediately said liquid stream.

5 above the body of liquid so that the stream Signed by me at Boston, Massachusetts,

will spread outwardly at the surface of the this twenty-fourth da of January 1918. liquid and carry any substances floating on WILLIAM BU TON WECOTT. 

